Related Experiment Video
Updated: Jul 18, 2026

Single-port Non-liposuction Endoscopic Axillary Lymph Node Dissection in Breast Cancer Surgery
Published on: April 3, 2026
Variant location of the musculocutaneous nerve during axillary nerve block
Steven L Orebaugh1, Scott Pennington
1Department of Anesthesiology, University of Pittsburgh Medical Center-Southside, Pittsburgh, PA 15203, USA. orebaughsl@anes.upmc.edu
Abstract:
We present the case of a 56-year-old man who underwent axillary nerve block for a wrist arthroscopy procedure, with real-time ultrasound and peripheral nerve stimulator guidance. The ulnar nerve and radial nerve were located medial and posterior to the brachial artery, respectively. A large complex structure was noted in the position typically occupied by the median nerve. Contact of this structure with the stimulating needle produced strong biceps contraction, and slight adjustment of the needle resulted in forearm pronation. After injection of 10 mL of local anesthetic near this structure, it appeared to consist of two separate components on ultrasound. We believe that these components represented the median and musculocutaneous nerves lying together, lateral to the artery. Radial, median, ulnar, and musculocutaneous nerve block ensued, and wrist arthroscopy was carried out uneventfully. Knowledge of this anatomical variation may improve anesthesiologists' ability to provide effective axillary block.
Related Concept Videos
Spinal Nerves: Plexus I
The Cervical Plexus
The cervical plexus, formed by the anterior rami of the first four...
Local Anesthetics: Differential Sensitivity of Nerve Fibers
Arteries of the Upper Limbs
Local Anesthetics: Clinical Application as Intravenous Regional Anesthesia
One of the advantages of...
Local Anesthetics: Clinical Application as Surface, Infiltration, and Conduction Block Anesthesia
Neuromuscular Junction And Blockade
